TABLE 5.

Correlation of mecA PCR test results with results of the oxacillin agar screen test

Organism group (no. of test results)	% Correct results by oxacillin screen plate manufacturer and inoculation methoda
	Remel				BDMS
	Wet		Expressed		Wet		Expressed
	24 h	48 h	24 h	48 h	24 h	48 h	24 h	48 h
S. epidermidis, mecA-positive (198)	62.6	81.3	52.0	74.2	22.2	54.5	15.7	38.9
Other species, mecA-positive (120)	59.2	73.3	50.0	64.2	51.7	73.3	45.0	61.7
S. epidermidis, mecA-negative (99)	100	100	100	100	100	100	100	99.0
Other species,bmecA-negative (129)	98.5	97.7	99.2	99.2	100	100	100	100

^aPercent correct results observed for each medium (growth for mecA-positive strains; no growth for mecA-negative strains). Wet, liquid was not expressed from the swab prior to inoculation of the agar screen plate; expressed, liquid was expressed from the swab prior to inoculation of the agar screen plate. 

^bData from three strains were deleted due to testing problems at one site.